package glassnodeapi import ( "bytes" "context" "encoding/json" "errors" "net/http" "net/url" "time" "github.com/c9s/requestgen" ) const defaultHTTPTimeout = time.Second * 15 const glassnodeBaseURL = "https://api.glassnode.com" type RestClient struct { BaseURL *url.URL Client *http.Client apiKey string } func NewRestClient() *RestClient { u, err := url.Parse(glassnodeBaseURL) if err != nil { panic(err) } client := &RestClient{ BaseURL: u, Client: &http.Client{ Timeout: defaultHTTPTimeout, }, } return client } func (c *RestClient) Auth(apiKey string) { c.apiKey = apiKey } func (c *RestClient) NewRequest(ctx context.Context, method string, refURL string, params url.Values, payload interface{}) (*http.Request, error) { body, err := castPayload(payload) if err != nil { return nil, err } rel, err := url.Parse(refURL) if err != nil { return nil, err } if params != nil { rel.RawQuery = params.Encode() } pathURL := c.BaseURL.ResolveReference(rel) return http.NewRequestWithContext(ctx, method, pathURL.String(), bytes.NewReader(body)) } func (c *RestClient) SendRequest(req *http.Request) (*requestgen.Response, error) { resp, err := c.Client.Do(req) if err != nil { return nil, err } defer resp.Body.Close() response, err := requestgen.NewResponse(resp) if err != nil { return response, err } // Check error, if there is an error, return the ErrorResponse struct type if response.IsError() { return response, errors.New(string(response.Body)) } return response, nil } func (c *RestClient) NewAuthenticatedRequest(ctx context.Context, method, refURL string, params url.Values, payload interface{}) (*http.Request, error) { rel, err := url.Parse(refURL) if err != nil { return nil, err } if params != nil { rel.RawQuery = params.Encode() } pathURL := c.BaseURL.ResolveReference(rel) path := pathURL.Path if rel.RawQuery != "" { path += "?" + rel.RawQuery } body, err := castPayload(payload) if err != nil { return nil, err } req, err := http.NewRequestWithContext(ctx, method, pathURL.String(), bytes.NewReader(body)) if err != nil { return nil, err } req.Header.Add("Content-Type", "application/json") req.Header.Add("Accept", "application/json") // Build authentication headers c.attachAuthHeaders(req, method, path, body) return req, nil } func (c *RestClient) attachAuthHeaders(req *http.Request, method string, path string, body []byte) { // Attch API Key to header. https://docs.glassnode.com/basic-api/api-key#usage req.Header.Add("X-Api-Key", c.apiKey) } func castPayload(payload interface{}) ([]byte, error) { if payload != nil { switch v := payload.(type) { case string: return []byte(v), nil case []byte: return v, nil default: body, err := json.Marshal(v) return body, err } } return nil, nil }